It's an ill wind that blows nobody some good...
(Tim, w/thanks to Scott) Being profoundly color blind, I've known it's not always a deficit. Here's a good article on the sexes, their senses and sense utilities (ahem) documenting what I've long known; that the ill wind of colorblindness does indeed blow us some good.
The story's told that, during the Second World War, the RAF had a small group of pilots they noted were quite good at spotting camouflage. When they looked into the matter, they found the thing this group of pilots had in common was that they were all color blind and had memorized the color charts to get into the RAF.
As the article puts it, "'Dichromads do better at tasks where color acts as a distraction,' in situations where spotting camouflaged objects is important, for example."